supernova
noun
Did you know?
A nova, despite its name, isn't actually a "new" star, but rather one that wasn't noticed until it exploded, when it may increase in brightness by a million times before returning to its previous state a few days later. A supernova is far larger; a star in its supernova state may emit a billion times as much light as previously. After a few weeks it begins to dim, until it eventually ceases to exist; it's often replaced by a black hole. (Though remains that were shot out into space may survive; those of a great supernova seen in A.D. 1054 are now known as the Crab Nebula.) All this may serve as a warning to those human stars whose fame explodes too rapidly; supernovas of this kind have sometimes vanished by the following year.
Examples of supernova in a Sentence
Matt Webb Mitovich, TVLine, 31 May 2025
Either way, supernovas produce a bevy of elements, from the lighter common ones to the rarer heavier ones.
—Robin George Andrews, Smithsonian Magazine, 30 May 2025
Both were focused on better understanding the demise of massive stars, but in one, the study was aimed at the sites of past supernovas (like NGC 4900) to estimate the masses of the stars that exploded and learn more about how the powerful events interact with their surroundings.
—Robert Z. Pearlman, Space.com, 24 Mar. 2025
These elements are thought to form through a series of nuclear reactions known as the rapid neutron capture process, or r-process, which was long theorized to occur only under extreme conditions such as those in supernovas or neutron star mergers.
—Victoria Corless, Space.com, 7 May 2025
See All Example Sentences for supernova
Cite this Entry
“Supernova.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/supernova. Accessed 6 Jun. 2025.
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supernova
noun
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